不完整约束蜗壳-水力联合作用及诱振机理研究

项目名称： 不完整约束蜗壳-水力联合作用及诱振机理研究

项目编号： No.51309128

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 水利工程

项目作者： 郭涛

作者单位： 昆明理工大学

项目金额： 25万元

中文摘要： 水力因素诱发的机组振动，不仅振源特性呈现出多样性和复杂性，其机理至今尚未完全清楚，而且机组刚度以及水工建筑物（基础）的结构形式和蜗壳埋设方式等对诱振和振动传递也有显著影响。预压蜗壳以其独特的结构优势在大中型水电站中已经得到越来越广泛的应用。然而不完整约束对蜗壳结构的受力性能也带来较大影响，尤其是考虑非均匀缝隙，对机组与外围混凝土之间的振动传递影响显著。本项目研究的核心内容就是弄清楚蜗壳结构在脱空、亚临界接触状态和联合工作状态下的蜗壳-水力耦合振动机理；研究高雷诺数旋转湍流场中流固体（流体+蜗壳）在欧拉、拉格朗日构架下的变形和动力学特征研究。建立求解此类蜗壳-水力联合作用所需的界面耦合程序的快速算法及高效的数值模拟技术的实现；结合振动传感试验，揭示蜗壳-水力相互作用的动力学机理。本项目研究对推进不完整约束蜗壳结构的水轮机稳定性分析方法体系的发展具有重要理论意义和应用价值。

中文关键词： 混流式水轮机；蜗壳；流固耦合；传力机制；不完整约束

英文摘要： In fluid-induced vibration of the hydro-turbine generating set, the vibrating source shows characteristics of the complexity and variety,while the mechanism has not been completely clear until now.The stiffness, the structrue form of the hydraulic building and the embedding manners of the spiral case have significant influences on the vibration and its transmitting. Due to its advantage of a special strcture,pre-load spiral case becomes more and more widely-used in the middle and big hydropower project.However,the nonholonomic constraint also plays an important role in affecting the mechanism, especially for the vibration transimitting between the spiral case and the external concrete when considering non-uniform cracks.The focus in this study are: obtain the spiral case-water coupling vibration mechanism in the separating, undercritical contact state and the co-work state; study the deformation and the dynamics of fluid-structure body(fluid and the spiral case)in rotating turbulent flow field with high Reynolds number;give the interface coupling program for the fast algorithm in solving this kind of interaction between the spiral case and water, and do numerical simulation with effective techniques;reveal the dynamic mechanism of the spiral case structure-water interaction with the combination of the vibrating

英文关键词： Francis turbine；Spiral case；Fluid-structure interaction；transmission mechanism；nonholonomic constraint